STEAM HACKED, USER DATABASE ACCESSED

Valve has taken the Steam Forums offline and Gabe Newell has posted a message explaining that Steam has been hacked.
On Sunday, the Steam Forums were defaced, but remained online. However, further investigation found the hack was more than just for the forum software, the intruder had also gained access to a Steam user database. On that database is the following information for customers of the digital gaming service:

• Usernames
• Hashed and salted passwords
• List of game purchases per user
• E-mail addresses
• Billing addresses
• Encrypted credit card details

Valve is currently investigating exactly what happened and specifically what information was accessed on the database. There is currently no evidence to suggest the user information has been taken, and nothing to confirm encrypted credit card details have somehow been decrypted.
Valve is going to force everyone to change their Steam Forum password when they decide to bring them back online as a security measure. Gabe has also apologized for what has happened and the inconvenience it is causing.
If you are one of the millions of Steam account holders out there, then be cautious and watch your credit card activity. If you shared your Steam Forum password with other services you use, then go change the password on those services immediately.